Process of impregnating wood.



UNITED snares PATENT curios.

JULIUS RIITGERS, OF BERLIN, GERMANY; ANDREAS COLLSTROP, OF COPENHAGEN, DEN- MARK, AND FRITZ NOEBE AND GUSTAV KRAEMER, OF BERLIN, GERMANY, EXEOUTORS OF SAID RIITGERS, DECEASED.

PROCESS OF IMPREGNATING WOOD;

Specification of Letters Patent.

Patented-Tilly 21, 1908.

Application filed ma 20, 1903. Serial No. 157,934..

To all whom it may concern:

Be it known that I, JULIUS Ri'ITeERs,

. manufacturer, a subject of the Emperor of Germany, and resident of Berlin W Prussia, German Empire, have invented an Improved Process for the Impregnation of VVood, of which the following is a specification.

In the ordinary process of impregnating wood, the wood after the air has been extracted from it more or less completely by means of a vacuum, is treated with the impregnating liquid or liqlpids by means of hydraulic pressure until t e pores of the wood have been filledor nearly filled, the object being to-introduce into the wood as much impregnating liquid as possible, after which the wood was considered ready for use.

This method has the defect, that the large quantity ofimpregnating liquid absorbed by the wood renders it unnecessarily heavy and increases the expense of the treatment.

The present invention has for its object, to effect the complete impregnation .of the wood by means of a comparatively small quantitv of impregnating liquid distributed in all cellulas throughout the wood up to the core. For this purpose the wood to be treated is placed in the impregnating cylinder 01' other closed receptacle, after which the impregnating liquid, such as tar oil or the like, which may be cold or warm, is caused to enter the cylinder until the cylinder is quite full.- Subseguently pressure is applied until the desire quantity of the impregnating liquid has entered the wood, after which the pres sure is taken off and the excess of impregnating li uid drawn off or discharged from the cylinder. Thereupon the wood lying in the cylinder is subjected to the action of sat urated or superheated steam (up to a a mospheres) or of hot gases under pressure or of a mixture of steam and hot gases under pressure, for a period depending on the nature and thickness of the wood (usually from 1 to 3 hours). Under the influence of heat and pressure the impregnating liquid which 1. The herein described process of pre-.

serving wood, which consists in immersing the wood in tar-oil, subjecting the tar oil with the wood to pressure, introducing an amount of tar-oil into the wood insufficient for filling all pores of the wood, drawing off the tar-oil surrounding the Wood and introducing a hot gaseous fluid under pressure into the Wood.

'2. The herein described process of preserving wood, which consists in immersing the wood in tar-oil, subjecting the tar-oil with the Wood to pressure, introducing an amount of tar-oil into the wood insufiicient for filling all pores of the wood, drawing ofi the tar oil surrounding the wood and introducing steam under pressure into the wood.

In testimony, that I claim the foregoing as my invention, I have signed my name in presence of two subscribing witnesses.

JULIUS RUTGERS.

Witnesses;

FRITZ NQEBE, EMIL FLoER. 

